Silicon single crystal antimony dopant preparation device and use method thereof

Abstract

The invention relates to the field of monocrystalline silicon preparation, in particular to a silicon single crystal antimony dopant preparation device and a use method thereof.The silicon single crystal antimony dopant preparation device comprises a base and a bottom arranged in a furnace body, a crucible is arranged at the top of the base, and an annular heating plate is arranged on the base and located on the periphery of the crucible; the first rotating mechanism is arranged at the bottom of the base, an output shaft of the first rotating mechanism is connected with the base, and the first rotating mechanism is used for driving the base and the crucible to horizontally rotate together; the mounting part is arranged in the auxiliary chamber and is connected with the auxiliary chamber through a vertical guide structure; the lifting mechanism is arranged on the auxiliary chamber, and the telescopic end of the lifting mechanism is connected with the mounting part; the second rotating mechanism is arranged on the mounting part, and the output end of the second rotating mechanism is connected with the seed crystal. The method can solve the problem that in the prior art, in the preparation and production process of monocrystalline silicon, the bud breaking phenomenon is likely to occur, and therefore it can be guaranteed that the radial uniformity of the electrical performance of the monocrystalline silicon is consistent.

Description

Technical Field

[0001] This invention relates to the field of single-crystal silicon preparation, and more specifically, to an apparatus for preparing antimony dopant in single-crystal silicon and a method for using the same. Background Technology

[0002] Silicon is the most common and widely used semiconductor material. When molten elemental silicon solidifies, silicon atoms arrange themselves into crystal nuclei in a diamond lattice. These nuclei grow into grains with the same crystal orientation, forming monocrystalline silicon. As a relatively reactive non-metallic element crystal, monocrystalline silicon is an important component of crystal materials and is at the forefront of new material development. The manufacturing process of monocrystalline silicon involves the following steps: quartz sand - metallurgical grade silicon - purification and refining - deposition of polycrystalline silicon ingots - monocrystalline silicon - silicon wafer cutting. Its main uses are as a semiconductor material and for solar photovoltaic power generation and heating.

[0003] A current apparatus for preparing silicon single-crystal antimony dopant includes a top-opening flask, an end cap, a support, and a combustion assembly. The end cap is fixed to the top of the flask to seal it, and its side is fixed to the top of the support. A support tube is fixed to the center of the top surface of the end cap, and the top surface of the end cap has an opening that matches the support tube. The top of the support tube is connected to an exhaust mechanism. An air inlet is opened on the end cap and connected to an air inlet pipe. Inside the flask, there is a fixed cylinder and a seed crystal. The fixed cylinder includes an upper insertion section and a lower fixing section. The insertion section is inserted into the support tube, and the seed crystal is inserted into the bottom of the fixing section and fixed. Air outlets are evenly distributed around the perimeter of the fixing section. The flask stores antimony crystals, which support the seed crystal. The combustion assembly is located below the flask to heat it. This apparatus avoids high-temperature damage by eliminating the need for a dedicated exhaust hose. The seed crystal is stably fixed, and its sinking position is automatically adjusted as the antimony melts to ensure solidification, saving time and effort. However, during implementation, the following problems were found with the existing technology: 1. In the existing process of preparing monocrystalline silicon, it is impossible to rotate the crucible and seed crystal. Most of them are stretched and grown by Czochralski, which leads to uneven temperature gradient at the solid-liquid interface of monocrystalline silicon and poor stability. This makes monocrystalline silicon prone to breakage during the preparation and production process, thus failing to ensure the radial uniformity of the electrical properties of monocrystalline silicon. 2. During the preparation of silicon single crystal antimony dopant, the crucible needs to be rotated. Existing preparation devices cannot fix the position of the crucible on the rotating stage. Usually, the crucible is placed directly on the rotating stage, which makes it easy for the crucible to be misaligned or displaced due to the vibration of the device, thus affecting the crystallization quality of single crystal silicon. Summary of the Invention

[0004] The purpose of this invention is to provide a silicon single crystal antimony dopant preparation device, which can solve the problem of bud breakage that easily occurs in the preparation and production process of single crystal silicon in the prior art, thereby ensuring the radial uniformity of the electrical properties of single crystal silicon.

[0005] Another objective of this invention is to provide a method for using a silicon single-crystal antimony dopant preparation apparatus, which can solve the problem of bud breakage that easily occurs during the preparation and production of single-crystal silicon in the prior art, thereby ensuring the radial uniformity of the electrical properties of single-crystal silicon.

[0006] The technical solution of this invention is implemented as follows: A silicon single-crystal antimony dopant preparation apparatus includes a shell assembly, which comprises a furnace body, a furnace cover disposed on top of the furnace body, and multiple support legs disposed on the bottom of the furnace body. A crucible is disposed inside the furnace body, and a secondary chamber is correspondingly disposed on the top of the furnace cover. The apparatus further includes: A base is located at the bottom of the furnace body, a crucible is placed on top of the base, and an annular heating plate is placed on the base and around the crucible. A first rotating mechanism is disposed at the bottom of the base, and the output shaft of the first rotating mechanism is connected to the base to drive the base and the crucible to rotate horizontally together. The mounting part is located inside the sub-chamber and is connected to the sub-chamber via a vertical guide structure; A lifting mechanism is installed on the auxiliary chamber. The telescopic end of the lifting mechanism is connected to the mounting part and is used to drive the mounting part to move vertically up and down in the auxiliary chamber. The second rotating mechanism is disposed in the mounting part. The output end of the second rotating mechanism is connected to the seed crystal and is used to drive the seed crystal to rotate horizontally in the crucible.

[0007] Further, the first rotating mechanism includes: The first bearing has a vertically opened first bearing mounting hole at the center of the bottom of the furnace body, and the first bearing is installed in the first bearing mounting hole. A connecting shaft is vertically installed inside the first bearing, and the upper end of the connecting shaft is fixedly connected to the base. The first motor is fixedly installed at the bottom center of the furnace body. The output shaft of the first motor is vertically installed facing upward and connected to the lower end of the connecting shaft through a coupling. The central axis of the output shaft of the first motor, the central axis of the crucible, and the central axis of the furnace body coincide. A groove is provided at the top center of the base, and a positioning seat for supporting the crucible is provided in the groove. Multiple positioning structures are provided between the outer side wall of the positioning seat and the inner side wall of the groove for positioning the positioning seat.

[0008] Furthermore, the positioning structure includes: The cavity is formed on the inner sidewall of the groove, and the two opposite inner walls of the cavity are formed with sliding grooves; A pressure plate is disposed in the cavity. Slider blocks that cooperate with the slide groove are respectively disposed on opposite sides of the pressure plate. A limiting part is provided at the outer port of the cavity to prevent the pressure plate from detaching from the cavity. An elastomer is disposed within the cavity and located between the bottom wall of the cavity and the pressure plate, for the pressure plate to reciprocate in a straight line; A positioning pin is provided on the outer side of the pressure plate; The positioning slot is provided on the outer side wall of the positioning seat, which matches the positioning pin. The positioning pin is inserted into the positioning slot for positioning between the base and the positioning seat.

[0009] Furthermore, both the groove and the positioning seat are rectangular structures, and their external dimensions are matched. The positioning base and the groove are provided with four sets of positioning structures on their four sides respectively, and the two sets of positioning structures arranged opposite each other are centrally symmetrical about the central axis of the base.

[0010] Furthermore, the vertical guide structure includes guide blocks and guide grooves, the inner wall of the auxiliary chamber has at least two guide grooves opened longitudinally, and the outer wall of the mounting part is provided with at least two guide blocks that slide in cooperation with the guide grooves.

[0011] Furthermore, the second rotating mechanism includes a second motor, a second bearing, and a rotating shaft; The mounting part is a plate-shaped structure, and a bearing hole for mounting a second bearing is provided in the middle. The rotating shaft is installed in the second bearing. A second motor is provided at the top center of the mounting part. The output shaft of the second motor is vertically downward and connected to the seed crystal through the rotating shaft.

[0012] Furthermore, the output shaft of the second motor is connected to the rotating shaft via a coupling, and the central axis of the output shaft of the second motor coincides with the central axis of the rotating shaft.

[0013] Furthermore, the lifting mechanism includes an electric push rod, a connecting block, a slide rod, and a connecting frame: The electric push rod is vertically installed on the outside of the sub-chamber. The telescopic end of the top of the electric push rod is connected to the connecting block. The connecting frame is fixedly connected to the mounting part. The sliding rod vertically passes through the top of the sub-chamber, and the upper and lower ends of the sliding rod are respectively connected to the connecting block and the connecting frame. The electric push rod is used to drive the mounting part to rise and fall in the vertical direction.

[0014] Furthermore, the furnace cover is also equipped with a gas filling valve and a vacuum extractor. The gas filling valve is used to introduce inert gas or nitrogen into the furnace body, and the vacuum extractor is used to create a vacuum inside the furnace body.

[0015] The method of using the aforementioned silicon single-crystal antimony dopant preparation apparatus includes the following steps: Place the crucible with the positioning seat into the groove of the base. The positioning seat presses the positioning pin and compresses the spring. When the positioning groove is aligned with the positioning pin, the positioning pin automatically engages with the positioning groove under the action of the spring force, thus achieving rapid positioning and fixation of the crucible. Add solid single-crystal silicon raw material to the crucible and close the furnace lid; After being evacuated by a vacuum pump, a protective inert gas is introduced through an argon filling valve. Turn on the annular heating plate to heat the silicon material in the crucible to a molten state; Control the electric push rod to slowly lower the seed crystal to the surface of the molten silicon. The first and second motors are started simultaneously and rotated in opposite directions.

[0016] The electric push rod controls the mounting part to rise slowly, pulling the seed crystal upwards, so that the molten silicon gradually crystallizes and grows into a single crystal silicon rod at the bottom of the seed crystal; Throughout the crystal pulling process, the counter-rotation of the crucible and the seed crystal works synergistically to maintain a uniform and stable temperature gradient at the solid-liquid interface, thus preventing crystal breakage. The rotation speed of the crucible driven by the first motor and the rotation speed of the seed crystal driven by the second motor can be independently adjusted according to different doping concentrations and crystal diameter requirements to optimize crystal growth quality.

[0017] Compared with the prior art, the beneficial effects of the present invention are: This solution provides an apparatus for preparing high-purity, high-quality antimony-doped single-crystal silicon. The crucible is fixed on a base, and the crucible and the seed crystal are rotated in opposite directions by a first rotating mechanism and a second rotating mechanism, respectively. This reverse rotation of the crucible and the seed crystal solves the problem of bud breakage that easily occurs during the preparation and production of single-crystal silicon in the prior art, thereby ensuring the radial uniformity of the electrical properties of single-crystal silicon. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a front view of the silicon single-crystal antimony dopant preparation apparatus of the present invention; Figure 2 This is an internal cross-sectional view of the silicon single-crystal antimony dopant preparation apparatus of the present invention; Figure 3for Figure 2 Enlarged structural diagram at point A in the middle; Figure 4 for Figure 2 Enlarged structural diagram at point B; Figure 5 This is a top-down view of the internal structure of the base.

[0020] In the picture: 1-Outer shell assembly; 101-Furnace body; 102-First motor; 103-Support leg; 2-Annular mounting seat; 3-Annular heating plate; 4-Connecting shaft; 5-Base; 6-Groove; 7-Cavity; 8-Slide groove; 9-Spring; 10-Pressure plate; 11-Slider; 12-Positioning pin; 13-Positioning seat; 14-Positioning groove; 15-Crucible; 16-Furnace cover; 17-Gas filling valve; 18-Secondary chamber; 19-Vacuum extractor; 20-Electric push rod; 21-Connecting block; 22-Slide rod; 23-Connecting frame; 24-Mounting part; 25-Second motor; 26-Guide block; 27-Rotating shaft; 28-Seed crystal; 29-Guide groove. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0023] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0024] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0025] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0026] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0027] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0028] Example 1 Please see Figures 1 to 5 A schematic diagram of a silicon single-crystal antimony dopant preparation apparatus is shown. The apparatus includes a housing assembly 1, which comprises a furnace body 101, a furnace cover 16 disposed on top of the furnace body 101, and multiple support legs 103 disposed on the bottom of the furnace body 101. A crucible 15 is disposed inside the furnace body 101, and a secondary chamber 18 is correspondingly disposed on the top of the furnace cover 16. The apparatus also includes: A base 5 is located at the bottom of the furnace body 101, a crucible 15 is located on the top of the base 5, and an annular heating plate 3 is located on the base 5 and around the crucible 15. A first rotating mechanism is disposed at the bottom of the base 5. The output shaft of the first rotating mechanism is connected to the base 5 and is used to drive the base 5 and the crucible 15 to rotate horizontally together. Mounting part 24, which is disposed inside the auxiliary chamber 18 and connected to the auxiliary chamber 18 through a vertical guide structure; A lifting mechanism is provided on the auxiliary chamber 18. The telescopic end of the lifting mechanism is connected to the mounting part 24 and is used to drive the mounting part 24 to move vertically up and down within the auxiliary chamber 18. The second rotating mechanism is disposed in the mounting part 24. The output end of the second rotating mechanism is connected to the seed crystal 28 and is used to drive the seed crystal 28 to rotate horizontally in the crucible 15.

[0029] In one optional implementation, the first rotating mechanism includes: The first bearing has a vertically opened first bearing mounting hole at the center of the bottom of the furnace body 101, and the first bearing is installed in the first bearing mounting hole. The connecting shaft 4 is vertically installed inside the first bearing, and the upper end of the connecting shaft 4 is fixedly connected to the base 5. The first motor 102 is fixedly installed at the bottom center of the furnace body 101. The output shaft of the first motor 102 is vertically installed facing upward and connected to the lower end of the connecting shaft 4 through a coupling. The central axis of the output shaft of the first motor 102, the central axis of the crucible 15, and the central axis of the furnace body 101 coincide. A groove 6 is provided at the top center of the base 5. A positioning seat 13 for supporting the crucible 15 is provided in the groove 6. Multiple positioning structures are provided between the outer side wall of the positioning seat 13 and the inner side wall of the groove 6 for positioning the positioning seat 13.

[0030] In one optional implementation, the positioning structure includes: Cavity 7, the inner sidewall of the groove 6 is formed by the cavity 7, and the two opposite inner walls of the cavity 7 are formed by the sliding grooves 8; A pressure plate 10 is disposed in the cavity 7. Slider blocks 11 that cooperate with the slide groove 8 are respectively disposed on opposite sides of the pressure plate 10. A limiting part is provided at the outer port of the cavity 7 to restrict the pressure plate 10 from leaving the cavity 7. An elastomer is disposed within the cavity 7 and located between the bottom wall of the cavity 7 and the pressure plate 10, for the pressure plate 10 to reciprocate in a straight line; Positioning pin 12 is provided on the outer side of pressure plate 10; The outer wall of the positioning seat 13 is provided with a positioning groove 14 that matches the positioning pin 12. The positioning pin 12 is inserted into the positioning groove 14 for positioning between the base 5 and the positioning seat 13.

[0031] Both the groove 6 and the positioning seat 13 are rectangular structures, and their external dimensions match. Four sets of positioning structures are respectively provided on the four sides of the positioning seat 13 and the groove 6, and the two sets of positioning structures that are set opposite to each other are arranged symmetrically about the central axis of the base 5.

[0032] In one optional embodiment, the vertical guide structure includes guide blocks 26 and guide grooves 29. At least two guide blocks 26 are longitudinally formed on the inner wall of the auxiliary chamber 18 and slide in cooperation with the guide grooves 29. At least two guide blocks 26 are provided on the outer wall of the mounting part 24 and slide in cooperation with the guide grooves 29.

[0033] In one optional embodiment, the second rotating mechanism includes a second motor 25, a second bearing, and a rotating shaft 27. The mounting portion 24 is a plate-like structure with a bearing hole in its middle for mounting the second bearing. The rotating shaft 27 is installed inside the second bearing. The second motor 25 is located at the top center of the mounting portion 24. The output shaft of the second motor 25 is vertically downward and connected to the seed crystal 28 through the rotating shaft 27. The output shaft of the second motor 25 is connected to the rotating shaft 27 via a coupling, and the central axis of the output shaft of the second motor 25 coincides with the central axis of the rotating shaft 27.

[0034] In one optional embodiment, the lifting mechanism includes an electric push rod 20, a connecting block 21, a slide rod 22, and a connecting frame 23: the electric push rod 20 is vertically arranged on the outside of the auxiliary chamber 18, the telescopic end of the top of the electric push rod 20 is connected to the connecting block 21, the connecting frame 23 is fixedly connected to the mounting part 24, the slide rod 22 vertically passes through the top of the auxiliary chamber 18, and the upper end and lower end of the slide rod 22 are respectively connected to the connecting block 21 and the connecting frame 23, and the electric push rod 20 is used to drive the mounting part 24 to rise and fall in the vertical direction.

[0035] In one optional embodiment, the furnace cover 16 is further equipped with a gas filling valve 17 and a vacuum extractor 19. The gas filling valve 17 is used to introduce high-purity inert gas or nitrogen into the furnace body 101, and the vacuum extractor 19 is used to create a vacuum inside the furnace body 101. In this embodiment, the gas filling valve 17 is used to introduce argon gas into the furnace body 101 to prevent the silicon material from oxidizing at high temperatures and to ensure the quality of crystal growth. The vacuum extractor 19 is connected to the furnace cavity through a pipe and is used to remove air from the furnace to establish a vacuum environment.

[0036] like Figure 1 As shown, the outer casing assembly 1 includes a furnace body 101, which is a sealed high-temperature resistant cavity 7, and can be made of stainless steel, possessing good airtightness and thermal stability. A first motor 102 is installed at the center of the bottom of the furnace body 101. The first motor 102 is a servo drive motor with precise speed adjustment function. Support legs 103 are fixed at the four corners of the bottom of the furnace body 101 to stably support the entire device on the working platform.

[0037] like Figure 2As shown, an annular mounting base 2 can also be fixedly provided on the inner wall of the furnace body 101. The annular mounting base 2 is arranged horizontally, and an annular heating plate 3 is fixedly installed at its top. The annular heating plate 3 is a graphite resistance heater or an induction heating coil, which is arranged around the outer periphery of the crucible 15. It can uniformly transfer heat to the crucible 15 after being energized, so as to achieve efficient and uniform heating and melting of the silicon material inside.

[0038] A connecting shaft 4 is vertically mounted on the bottom of the furnace body 101 via a bearing. The lower end of the connecting shaft 4 is connected to the output shaft of the first motor 102, and the upper end is fixedly connected to the bottom center of the base 5. The base 5 is located in the lower part of the furnace cavity, and its top end has a groove 6. The groove 6 has a rectangular structure and its size matches the positioning seat 13 to achieve a precise embedding fit.

[0039] like Figure 4 and Figure 5 As shown, the four walls of the groove 6 in the base 5 are respectively provided with cavities 7, each cavity 7 extending radially. Slide grooves 8 are symmetrically provided on the inner walls of both sides of each cavity 7, and the slide grooves 8 are linear guide rail structures. A spring 9 is fixedly connected to one end of a cavity 7, and the other end of the spring 9 is connected to a pressure plate 10. Sliders 11 are provided at both ends of the pressure plate 10. The sliders 11 are embedded in the slide grooves 8 and can slide along their length, thereby ensuring that the pressure plate 10 moves smoothly and without deflection.

[0040] A positioning pin 12 is fixed on the side of the pressure plate 10 away from the spring 9, and the positioning pin 12 extends toward the center of the groove 6. The spring 9, pressure plate 10 and positioning pin 12 in the four cavities 7 are symmetrically distributed about the central axis of the base 5, forming a four-point elastic clamping mechanism.

[0041] The positioning seat 13 is a rectangular structure adapted to the shape of the groove 6 and is embedded inside the groove 6. Positioning grooves 14 are correspondingly formed on the four outer walls of the positioning seat 13. When the positioning seat 13 is inserted into the groove 6, the positioning grooves 14 align with the positioning pin 12. As the insertion process progresses, the positioning seat 13 presses against the positioning pin 12, causing it to drive the pressure plate 10 to compress the spring 9 and retract into the cavity 7. When the positioning groove 14 moves to align with the positioning pin 12, under the restoring force of the spring 9, the positioning pin 12 automatically pops out and locks into the positioning groove 14, forming a reliable mechanical locking structure. This achieves rapid installation and secure fixation of the crucible 15, preventing displacement or tilting due to vibration during rotation.

[0042] The crucible 15 is placed on top of the positioning base 13 and is used to hold solid single-crystal silicon raw materials and antimony dopants. The crucible 15 is usually made of high-purity quartz or graphite material, which is heat-resistant and chemically stable.

[0043] The auxiliary chamber 18 is located on one side of the center of the furnace cover 16. It has a hollow internal structure, running vertically through the furnace cavity. An electric push rod 20 is installed on one outer wall of the auxiliary chamber 18. The electric push rod 20 is a precision linear actuator, and its stroke and speed can be adjusted via a controller. The extended end of the electric push rod 20 is connected to one side of a connecting block 21, while the other side of the connecting block 21 is connected to a sliding rod 22. The sliding rod 22 extends vertically downwards and passes through the top of the auxiliary chamber 18 into its interior.

[0044] The bottom end of the slide rod 22 is fixedly connected to the top of the connecting frame 23. The connecting frame 23 is a U-shaped bracket, and its bottom end is fixedly connected to both sides of the top of the mounting part 24. The mounting part 24 has a horizontal plate-like structure and can be vertically raised and lowered within the auxiliary chamber 18.

[0045] A second motor 25 is fixedly installed at the top center of the mounting section 24. The second motor 25 is a high-precision closed-loop control motor with constant speed, variable speed and reverse rotation capabilities. Guide blocks 26 are also provided at both ends of the mounting section 24. The guide blocks 26 are embedded in the guide grooves 29 opened in the inner wall of the auxiliary chamber 18. The two form a sliding fit relationship to ensure that the mounting section 24 maintains a horizontal posture during the lifting process and avoids shaking or jamming.

[0046] A rotating shaft 27 is vertically mounted at the bottom center of the mounting section 24 via a bearing. The upper end of the rotating shaft 27 is connected to the output shaft of the second motor 25 for transmission, and the lower end is fixedly connected to the seed crystal 28. The second motor 25 is a servo motor. The seed crystal 28 is a polished single-crystal silicon rod, which serves as the starting core for crystal growth.

[0047] The central axis of the first motor 102, the connecting shaft 4, the base 5, the crucible 15, and the central axes of the furnace body 101 and the auxiliary chamber 18 are collinear, and are coaxial with the rotation axis 27 of the second motor 25, the rotating shaft 27, and the seed crystal 28, to ensure the concentricity and stability of the rotational motion.

[0048] In summary, the functions of each component in this scheme are as follows: The outer casing assembly 1 provides a sealed, high-temperature resistant cavity 7, supporting all internal components; the furnace body 101 is made of stainless steel, with strong airtightness and can withstand high temperature and pressure; the first motor 102 drives the crucible 15 to rotate, with servo control of speed and start / stop; the support legs 103 stabilize the entire machine and reduce vibration and noise; the annular mounting base 2 fixes the annular heating plate 3, maintaining coaxiality; the annular heating plate 3 provides uniform circumferential heating of the crucible 15, avoiding localized overheating; the connecting shaft 4 drives the motor and the base 5, transmitting torque; the base 5 supports the crucible 15 and is internally mounted. A four-way elastic clamping mechanism (i.e., positioning structure); a groove 6 accommodates a positioning seat 13, and its rectangular structure ensures positioning accuracy; a cavity 7 houses a spring 9 and a pressure plate 10, providing travel space for the positioning pin 12; a slide 8 restricts the movement trajectory of the pressure plate 10 to prevent tilting and jamming; the spring 9 provides restoring force, driving the positioning pin 12 to automatically lock; the pressure plate 10 transmits elastic force, causing the positioning pin 12 to extend and retract; a slider 11 cooperates with the slide 8 to achieve linear guiding motion; the positioning pin 12 inserts into the positioning groove 14 to complete mechanical locking; and a positioning seat. 13, fixed to the bottom of crucible 15, with positioning groove 14; positioning groove 14 matches positioning pin 12 to achieve snap-fit ​​locking; crucible 15 holds silicon material and antimony dopant and participates in rotation; furnace cover 16 seals the furnace cavity and integrates gas and transmission interfaces; gas filling valve 17 injects high-purity argon gas to prevent oxidation; auxiliary chamber 18 houses the lifting mechanism and isolates the main cavity from contamination; vacuum pump 19 evacuates the furnace body 101 to establish a clean growth environment; electric push rod 20 drives the seed crystal 28 to rise and fall, precisely controlling the pulling speed; connecting block 21 The system connects the electric push rod 20 and the slide rod 22; the slide rod 22 transmits the thrust to the connecting frame 23; the connecting frame 23 connects the slide rod 22 and the mounting part 24; the mounting part 24 supports the servo motor and the rotating shaft 27; the second motor 25 drives the seed crystal 28 to rotate, and can be rotated in both directions with adjustable speed; the guide block 26 slides in the guide groove 29 to ensure smooth lifting; the rotating shaft 27 transmits torque to the seed crystal 28; the seed crystal 28 is the starting point of crystal growth and participates in rotation and lifting; the guide groove 29 cooperates with the guide block 26 to guide the vertical movement of the mounting part 24.

[0049] This solution also provides a method for preparing silicon single-crystal antimony dopant based on the above-mentioned device, the specific operation steps of which are as follows: 1. Equipment preparation and installation: Place the device on a flat and stable workbench and check that all parts are securely connected; open the furnace cover 16 and slowly place the crucible 15 with the positioning seat 13 into the groove 6 of the base 5 from above; as the positioning seat 13 moves down, its outer wall pushes the four positioning pins 12 to compress the spring 9 until the positioning groove 14 is aligned with the positioning pins 12. Under the restoring force of the spring 9, the positioning pins 12 automatically engage with the positioning groove 14 to complete the locking, thus achieving rapid and stable fixation of the crucible 15; 2. Feeding and sealing: Add a certain amount of high-purity solid single crystal silicon raw material and a predetermined proportion of antimony dopant particles to crucible 15, and close furnace cover 16 to ensure good sealing; 3. Vacuuming and Gas Filling: Start the vacuum pump 19 to extract the air from the furnace chamber and achieve the preset vacuum level (e.g., 10). - (on the order of 2Pa); then high-purity argon gas is introduced through gas filling valve 17 to maintain a positive pressure inert atmosphere inside the furnace and prevent material oxidation; 4. Heating and melting: Turn on the annular heating plate 3 and gradually raise the temperature to above the melting point of silicon (about 1420°C) to completely melt the silicon material in the crucible 15 and form a uniform molten silicon liquid; during this process, the crucible 15 can be kept stationary or pre-rotated at a low speed to promote uniform temperature field. 5. Crystal pulling and seeding: Adjust the height of the mounting section 24 so that the bottom of the seed crystal 28 gently contacts the surface of the molten silicon; at this time, the first motor 102, the second motor 25, and the electric push rod 20 are simultaneously started via the controller: The first motor 102 drives the connecting shaft 4 to rotate the base 5 and crucible 15 clockwise. The second motor 25 drives the rotating shaft 27 to rotate the seed crystal 28 counterclockwise; The rotation speeds of both can be adjusted independently according to process requirements. Under typical conditions, the crucible 15 rotates at 5~20 rpm, and the seed crystal 28 rotates at 10~30 rpm, in opposite directions. The dual reverse rotation design enables controllable shear flow between the melt and the seed crystal 28, effectively improving the thermal and flow field distribution at the solid-liquid interface and significantly enhancing the uniformity and stability of the temperature gradient. 6. Continuous pulling growth: The electric push rod 20 slowly extends upward, and through the connecting block 21, slide rod 22, and connecting frame 23, it drives the mounting part 24 to rise steadily along the guide groove 29, thereby pulling the seed crystal 28 and the grown single crystal silicon rod gradually out of the melt; throughout the crystal pulling process, the second motor 25 continuously drives the seed crystal 28 to rotate counterclockwise, and the first motor 102 continuously drives the crucible 15 to rotate clockwise, forming a dynamically balanced crystal growth environment; 7. Crystallization completion and cooling: After the monocrystalline silicon rod grows to the target length, stop heating, close the annular heating plate 3, and continue to slowly raise the seed crystal 28 while reducing the rotation speed to complete the finishing process; after the furnace has cooled naturally to a safe temperature, open the furnace cover 16 and take out the finished monocrystalline silicon ingot.

[0050] This solution significantly optimizes the thermodynamic conditions of the solid-liquid interface during single-crystal silicon growth by setting up a dual-rotation system—a synergistic mechanism of clockwise rotation of crucible 15 and counterclockwise rotation of seed crystal 28. This avoids the "bud breakage" phenomenon caused by uneven temperature gradients and improves crystal integrity. At the same time, the elastic positioning structure of spring 9, pressure plate 10, and positioning pin 12 enables rapid clamping and vibration-resistant fixation of crucible 15, greatly improving equipment operation stability and product consistency.

[0051] Furthermore, the cooperation between the guide groove 29 and the guide block 26 ensures the linearity and stability of the seed crystal 28's lifting process; the annular heating plate 3 provides circumferential uniform heating; and the fully enclosed inert atmosphere environment ensures the purity of the material. In summary, the silicon single crystal antimony dopant preparation apparatus and method provided by this invention are suitable for large-scale, high-quality industrial production of heavily antimony-doped single crystal silicon, meeting the stringent requirements of semiconductor devices for radial uniformity of electrical performance.

[0052] Example 2 A method of using a silicon single-crystal antimony dopant preparation apparatus, comprising the following steps: The crucible 15 with the positioning seat 13 is placed into the groove 6 of the base 5. The positioning seat 13 presses the positioning pin 12 and compresses the spring 9. When the positioning groove 14 is aligned with the positioning pin 12, the positioning pin 12 automatically engages with the positioning groove 14 under the elastic force of the spring 9, thus achieving rapid positioning and fixation of the crucible 15. Add solid single-crystal silicon raw material to crucible 15 and close furnace lid 16; After being evacuated by the vacuum pump 19, protective inert gas is introduced through the gas filling valve 17. Activate the annular heating plate 3 to heat the silicon material in the crucible 15 to a molten state; Control the electric push rod 20 to move, so that the seed crystal 28 slowly descends to the surface of the molten silicon; The first motor 102 and the second motor 25 are started synchronously and rotated in opposite directions.

[0053] The first motor 102 drives the base 5 and the crucible 15 to rotate clockwise via the connecting shaft 4; The second motor 25 drives the seed crystal 28 to rotate counterclockwise via the rotating shaft 27; The electric push rod 20 controls the mounting part 24 to rise slowly, driving the seed crystal 28 to be pulled upward, so that the molten silicon gradually crystallizes and grows into a single crystal silicon rod at the bottom of the seed crystal 28; Throughout the crystal pulling process, the counter-rotation of crucible 15 and seed crystal 28 works synergistically to maintain a uniform and stable temperature gradient at the solid-liquid interface, thus preventing crystal breakage. The rotation speeds of crucible 15 and seed crystal 28 can be independently adjusted according to different doping concentrations and crystal diameter requirements to optimize crystal growth quality.

[0054] Antimony doping is achieved by pre-mixing a certain amount of high-purity antimony powder into solid silicon raw materials, or by adding a certain amount of antimony element source to molten silicon through a feeding device during the melting process.

[0055] The beneficial effects of the technical solution of the present invention are: 1. Significantly improves the temperature field distribution at the solid-liquid interface and enhances crystal growth stability. This solution employs a "dual reverse rotation" synergistic control strategy, combining clockwise rotation of crucible 15 with counterclockwise rotation of seed crystal 28. This breaks away from the natural convection vortex structure of the traditional unidirectional or static crucible 15 mode, creating a spiral shear flow field within the melt to effectively regulate heat conduction and convection paths. The rotation of crucible 15 drives the movement of the surrounding melt, enhancing circumferential heat exchange. The counterclockwise rotation of seed crystal 28 generates disturbance in the central region, breaking the boundary layer thermal resistance. The bidirectional shearing action ensures uniform radial diffusion of heat, preventing local overheating or cold zone accumulation, resulting in an extremely low breakage rate, improving product yield and quality, and ensuring high crystal integrity to meet the needs of high-end applications.

[0056] 2. Significantly improves the positioning accuracy and vibration resistance of crucible 15, ensuring consistent crystallization quality. In traditional equipment, the crucible 15 is mostly installed in a "placement" manner, lacking an effective locking mechanism. Under the influence of high temperature, high speed rotation, and thermal expansion, it is prone to displacement, tilting, or even slippage. This invention innovatively designs an elastic self-locking positioning system based on spring 9, pressure plate 10, and positioning pin 12. Combined with the guiding structure of rectangular groove 6 and positioning seat 13, it achieves mechanically precise fixing. After the positioning seat 13 is inserted into the groove 6, it automatically triggers the positioning pin 12 to lock into the positioning groove 14. The four-point symmetrical spring 9 applies force to provide uniform clamping force. The slider 11 and the slide groove 8 restrict the direction of movement to prevent the pressure plate 10 from tilting and jamming. The entire process does not require bolt tightening, achieving rapid assembly and disassembly.

[0057] 3. Optimize the overall equipment operation stability and automation level. This solution is equipped with a multi-guide and synchronous control system: the guide block 26 and the guide groove 29 form a double-sided limiting pair to ensure that the seed crystal 28 is straight and without sway during the lifting process; the electric push rod 20 drives the connecting frame 23 to achieve smooth lifting and avoid impact loading; all motors (first motor 102, second motor 25, electric push rod 20) can be linked and programmed for control through a PLC controller or industrial computer.

[0058] 4. Improve equipment safety and ease of maintenance Good sealing: The fully enclosed furnace body 101, combined with the vacuum extractor 19 and argon protection system, effectively prevents oxidation and impurity contamination; Modular design: The crucible 15 fixing mechanism, lifting system, and heating system can all be independently inspected and replaced; Comprehensive safety protection: It is equipped with over-temperature alarm, overload protection, abnormal displacement detection and other functional interfaces; Extended life of key components: Due to reduced vibration, the wear rate of mechanical parts such as bearings and drive shafts is reduced.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for preparing a silicon single crystal antimony dopant, comprising a housing assembly (1), the housing assembly (1) comprising a furnace body (101), a furnace cover (16) arranged on the top of the furnace body (101), and a plurality of supporting legs (103) arranged on the bottom of the furnace body (101), a crucible (15) being arranged in the furnace body (101), and a sub-chamber (18) being arranged on the top of the furnace cover (16), characterized in that, Also include: The base (5) is arranged at the bottom of the furnace body (101), the top of the base (5) is provided with a crucible (15), and the annular heating plate (3) is arranged on the base (5) and located at the periphery of the crucible (15); The first rotating mechanism is arranged at the bottom of the base (5), the output shaft of the first rotating mechanism is connected with the base (5), and the base (5) and the crucible (15) are driven to rotate horizontally; The mounting portion is arranged inside the sub-chamber (18) and connected with the sub-chamber (18) through a vertical guide structure; The lifting mechanism is arranged on the sub-chamber (18), the telescopic end of the lifting mechanism is connected with the mounting portion, and the mounting portion is driven to vertically lift in the sub-chamber (18); The second rotating mechanism is arranged on the mounting portion, the output end of the second rotating mechanism is connected with the seed crystal (28), and the seed crystal (28) is driven to rotate horizontally in the crucible (15).

2. The apparatus for preparing a silicon single crystal antimony dopant according to claim 1, wherein The first rotating mechanism comprises: The first bearing is vertically arranged in the center of the bottom of the furnace body (101), and the first bearing is correspondingly arranged in the first bearing mounting hole; The connecting shaft (4) is vertically arranged in the first bearing, and the upper end of the connecting shaft (4) is fixedly connected with the base (5); The first motor (102) is fixedly arranged at the bottom center of the furnace body (101), the output shaft of the first motor (102) is vertically arranged upwards and connected with the lower end of the connecting shaft (4) through a shaft coupling; Wherein, the center axis of the output shaft of the first motor (102), the center axis of the crucible (15) and the center axis of the furnace body (101) coincide, the top center of the base (5) is provided with a groove (6), the positioning seat (13) for supporting the crucible (15) is arranged in the groove (6), and a plurality of positioning structures are arranged between the outer side wall of the positioning seat (13) and the inner side wall of the groove (6) for positioning the positioning seat (13).

3. The apparatus for preparing a silicon single crystal antimony dopant according to claim 2, wherein The positioning structure comprises: The cavity (7) is arranged in the inner side wall of the groove (6), and the relative two inner walls of the cavity (7) are provided with the sliding groove (8); The pressing plate (10) is arranged in the cavity (7), the relative two sides of the pressing plate (10) are respectively provided with the sliding block (11) matched with the sliding groove (8), and the outer end of the cavity (7) is provided with a limiting portion for limiting the pressing plate (10) from separating from the cavity (7); The elastic body is arranged in the cavity (7) and between the bottom wall of the cavity (7) and the pressing plate (10), and the pressing plate (10) is arranged in the cavity (7) and between the bottom wall of the cavity (7) and the pressing plate (10); The positioning pin (12) is arranged on the outer side of the pressing plate (10); The positioning groove (14) is arranged in the outer side wall of the positioning seat (13) and matched with the positioning pin (12), the positioning pin (12) is inserted into the positioning groove (14), and the positioning between the base (5) and the positioning seat (13) is realized.

4. The apparatus for preparing a silicon single crystal antimony dopant according to claim 3, wherein The groove (6) and the positioning seat (13) are both rectangular structures, and the outer dimensions of the two are matched. Four groups of the positioning structures are arranged on four sides of the positioning seat (13) and the groove (6) respectively, and two groups of the positioning structures arranged oppositely are arranged in a central symmetry about the central axis of the base (5).

5. The apparatus for preparing a silicon single crystal antimony dopant of claim 1, wherein the silicon single crystal antimony dopant preparation device is characterized by, The vertical guide structure comprises guide blocks (26) and guide grooves (29), and the inner wall of the sub-chamber (18) is longitudinally provided with at least two guide grooves (29), and the outer wall of the mounting portion is provided with at least two guide blocks (26) in sliding fit with the guide grooves (29).

6. The apparatus for preparing a silicon single crystal antimony dopant according to claim 1, wherein The second rotating mechanism comprises a second motor (25), a second bearing and a rotating shaft (27). The mounting portion (24) is in a plate structure, and a bearing hole for mounting the second bearing is formed in the middle portion of the mounting portion, the rotating shaft (27) is mounted in the second bearing, the second motor (25) is arranged at the top center of the mounting portion, and the output shaft of the second motor (25) is vertically downward and connected with the rotating shaft (27) to connect the seed crystal (28).

7. The apparatus for preparing a silicon single crystal antimony dopant according to claim 6, wherein The output shaft of the second motor (25) is connected with the rotating shaft (27) through a shaft coupling, and the central axis of the output shaft of the second motor (25) coincides with the central axis of the rotating shaft (27).

8. The apparatus for preparing a silicon single crystal antimony dopant according to claim 1, wherein The lifting mechanism comprises an electric push rod (20), a connecting block (21), a sliding rod (22) and a connecting frame (23). The electric push rod (20) is vertically arranged outside the sub-chamber (18), the telescopic end of the top end of the electric push rod (20) is connected with the connecting block (21), the connecting frame (23) is fixedly connected with the mounting portion (24), the sliding rod (22) vertically penetrates the top of the sub-chamber (18), and the upper end and the lower end of the sliding rod (22) are connected with the connecting block (21) and the connecting frame (23) respectively, and the electric push rod (20) is used for driving the mounting portion (24) to lift in the vertical direction.

9. The apparatus for preparing a silicon single crystal antimony dopant according to claim 1, wherein The furnace cover (16) is further provided with a gas filling valve (17) and a vacuum extractor (19), the gas filling valve (17) is used for introducing inert gas or nitrogen into the furnace body (101), and the vacuum extractor (19) is used for vacuumizing the furnace body (101).

10. A method of using a device for producing a silicon single crystal antimony dopant as claimed in any one of claims 1 to 9, characterized in that The method comprises the following steps: The crucible (15) with the positioning seat (13) is placed in the groove (6) of the base (5), the positioning pin (12) is pressed and the spring (9) is compressed through the positioning seat (13), when the positioning groove (14) is aligned with the positioning pin (12), the positioning pin (12) is automatically clamped into the positioning groove (14) to realize the rapid positioning and fixing of the crucible (15) under the elastic force of the spring (9); Solid single crystal silicon raw materials are added into the crucible (15), and the furnace cover (16) is closed; After vacuumizing through the vacuum extractor (19), protective inert gas is filled through the gas filling valve (17); The annular heating plate (3) is started to heat the silicon materials in the crucible (15) to a molten state; The electric push rod (20) is controlled to act, so that the seed crystal (28) slowly descends to contact the surface of the molten silicon liquid; The first motor (102) and the second motor (25) are started synchronously and rotated in opposite directions; The electric push rod (20) controls the slow rising of the mounting part (24) to pull up the seed crystal (28) and make the molten silicon crystallize into a single crystal silicon rod at the bottom of the seed crystal (28); During the whole crystal pulling process, the reverse rotation of the crucible (15) and the seed crystal (28) cooperates to keep the solid-liquid interface temperature gradient uniform and stable, avoids the occurrence of the broken sprout phenomenon, and the rotation speed of the crucible (15) driven by the first motor (102) and the rotation speed of the seed crystal (28) driven by the second motor (25) can be independently adjusted according to different doping concentrations and crystal diameter requirements to optimize the crystal growth quality.

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